#include<stdio.h>
long f( int g)
{ 
switch(g)
 { case 0:return 0;
 case 1:
 case 2: return 1; 
 }
 return (f(g-1)+f(g-2));
}
int main ( )
{ long k;
 k = f(7);
printf("k= %d\n",k);
return 0;
}